[Bone cements based on polymethylmethacrylate]

Bone cements based on polymethylmethacrylate (PMMA) remain an important material for anchorage of artificial joints. Polymers based on PMMA originally developed for dental surgery have been successfully used in bone surgery for more than 40 years. At first sight the cold-curing PMMA bone cement seems to be a rather simple material consisting of a powder and a liquid. But in fact it is a complex material fulfilling various functions at its application site after the implantation. Its properties vary according to the composition of its basic elements. They already play a decisive role for the working behavior during mixing of both components. The differences in the working behavior considerably affect the cementing technique and the accurate application in vivo. These influence the mechanical performance of the cured cement mantle and the long-term results of the implantation. Standardized test methods are used to characterize bone cements,whereas the clinical relevance of the test methods has to be evaluated critically.Additionally,PMMA bone cements act as a drug delivery system as a local carrier of antibiotics. This paper gives a review of the composition and properties of PMMA bone cements and their influence on practical application.